Play structures, in particular, are often formed so that they can be transformed quickly from an erect condition for use, to a compact collapsed condition for storage. Many such structures include rigid support rods which must be assembled and dismantled, or are of the so-called pop-up kind and include cobble steel frame sections which when released from storage spring into an erect condition to support the structure, the steel sections being contained within sleeves to which are welded or stitched flexible webs of material forming the walls and roof of the structure.
An object of the present invention is to provide a structure which performs in a similar manner but which is transformed into its erect condition by inflation of one or more tubular sections forming a framework for the structure and to which are attached flexible webs to form, for example, walls and/or roof, and possibly also a base or groundsheet. Avoidance of the use of supports rods or steel frame sections results in the structure being lighter in weight and collapsible to a more compact form.
U.S. Pat. No. 4,068,418 discloses a tent transformable by inflation from a collapsed condition for storage to an erect condition for use, the tent comprising an inflatable tubular framework, which when inflated supports the structure in its erect condition, and a flexible wall structure attached to and extending between two or more regions of said inflatable framework. The inflatable tubular framework comprises a plurality of inflatable tubular elements, each of flexible, elastic, air-impermeable material and having a respective inflation valve, and each fitted inside a respective outer sheath of a material which is flexible but non-elastic. Each inflatable tubular element, when inflated, is a snug fit within its respective outer sheath and thereby restrained in outward expansion and prevented from rupturing. The inflatable tubular elements are formed by extrusion from thermoplastic material, such as PVC, and the outer sheaths are formed as separate curving sheaths which are separately cut to shape from woven material and stitched. Four such structural sections, each formed of an inflatable element inside its outer sheath provide four parabolic corner posts radiating out and down from a connector at a centre top location of the tent.